Microcapsule: Case Study: Encapsulation

In November 2007, a research group at Carnegie Mellon University announced they had developed microcapsules capable of delivering genetically engineered adult neural stem cells into the brain where they then produce an essential enzyme.

When such cells are re-implanted without a microcapsule, they elicit an inflammatory response, which causes them to differentiate into mature cells, rather than disperse throughout the brain.

The group, led by Prof Stefan Zappe and Dr Raymond Sekula were able to harvest adult neural cells, genetically engineer them, cause them to multiply outside the body, surgically implant the microcapsule in the brain and cause the cells to disperse once the outer casing of the microcapsule had been degraded
The degradation of the capsule is done by engineering the stem cells to produce a degrading enzyme.

Once outside the capsule the cells migrate into the surrounding brain tissue and produce the enzyme of choice, iduronate-2-sulfatase, which is absent in patients with Hunter’s syndrome Interestingly, the microcapsules can be instructed to allow the cells inside to proliferate, differentiate or migrate. The capsules can also control the extent of the migration The goal of the research is to genetically engineer neural cells from the patient, re-implant them and remotely control their actions in non-invasive ways.